Serious dry firing develops grip, trigger finger placement, sight alignment and trigger release. When I was shooting on several Marine Corps rifle and pistol teams I dry fired this way for about thirty minuets a day: some times longer

I placed a kitchen chair with its back facing me about ten feet form a blank white wall with no target. The chair simulates the firing line bench. With the pistol resting on the back of the chair I got my grip, placed my finger on the trigger, focused my eyes on the front sight and raised the pistol. Next I aligned the sights on the wall and released the trigger. Any disturbance of my sight alignment from my trigger release was apperant.